US8362808B2 - Transmission input circuit - Google Patents

Transmission input circuit Download PDF

Info

Publication number
US8362808B2
US8362808B2 US13/121,866 US200913121866A US8362808B2 US 8362808 B2 US8362808 B2 US 8362808B2 US 200913121866 A US200913121866 A US 200913121866A US 8362808 B2 US8362808 B2 US 8362808B2
Authority
US
United States
Prior art keywords
current
transmission
current detection
voltage
input
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active, expires
Application number
US13/121,866
Other languages
English (en)
Other versions
US20110187415A1 (en
Inventor
Mitsuhiro Kurimoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hochiki Corp
Original Assignee
Hochiki Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hochiki Corp filed Critical Hochiki Corp
Assigned to HOCHIKI CORPORATION reassignment HOCHIKI CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: KURIMOTO, MITSUHIRO
Publication of US20110187415A1 publication Critical patent/US20110187415A1/en
Application granted granted Critical
Publication of US8362808B2 publication Critical patent/US8362808B2/en
Active legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08C—TRANSMISSION SYSTEMS FOR MEASURED VALUES, CONTROL OR SIMILAR SIGNALS
    • G08C19/00—Electric signal transmission systems
    • G08C19/02—Electric signal transmission systems in which the signal transmitted is magnitude of current or voltage
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B17/00—Fire alarms; Alarms responsive to explosion
    • G08B17/12—Actuation by presence of radiation or particles, e.g. of infrared radiation or of ions
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
    • G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
    • G08B25/06—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using power transmission lines
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
    • G08B29/18—Prevention or correction of operating errors
    • G08B29/183—Single detectors using dual technologies

Definitions

  • Sensor lines 108 a and 108 b are led out from the relay device 106 , and a plurality of ON/OFF type sensors 110 which do not have a transmitting function, are connected thereto as loads.
  • the ON/OFF type sensor 110 detects an indication of a fire hazard occurrence, it allows an alarm current to flow to the relay device 106 via the sensor lines 108 a and 108 b .
  • the relay device 106 receives this alarm current, fire hazard alarm data is transmitted from the relay device 106 to the receiver device 100 . Then, the receiver device 100 issues a fire hazard warning.
  • the relay device 106 and the analog type sensor 104 are connected to the transmission lines 102 a and 102 b , and a load current Iz dependant on the load 122 of the relay device 106 is flowed at an empty timing where no transmission current is flowing.
  • a transmission current Ia with the load current Iz added thereto flows.
  • a detection voltage according to the line current which is produced at both ends of the current detection resistor R 11 shown in FIG. 8 is applied to the negative input terminal of a comparator 122 .
  • a capacitor C 11 is connected to the positive input terminal of the comparator 122 , and the capacitor C 11 is further connected to the input side of the diode D 11 via a switch SW 11 .
  • FIG. 9 is a time chart showing a signal waveform of each section in FIG. 8 .
  • FIG. 9 (A) shows the input voltage of the comparator 122
  • FIG. 9 (B) shows the timing of sampling of the capacitor C 11 performed by the switch SW 11 .
  • a transmission current Ia flows due to transmission of a transmission signal from a slave device, at the current detection resistor R 11 , there is produced a transmission current detection voltage Va corresponding to the transmission current Ia, having the load current detection voltage Vz added thereto.
  • the present invention takes consideration the above circumstances, with an object of providing a transmission input circuit in which a threshold voltage for detecting transmission current can be arbitrarily set, and no variation occurs therein due to temperature, enabling an accurate detection of transmission current.
  • the present invention employs following measures.
  • a transmission input circuit of a master device which, in a state where a load current from a load is flowing into a transmission line serving also as a power supply line, detects the presence or absence of a transmission current from a slave device connected to the transmission line, the transmission input circuit being provided with: a current detection resistor which receives an input of a line current flowing through the transmission line and generates a line current detection voltage; a constant current circuit which generates a predetermined reference current; a first switch which performs a switching operation at an empty timing where the transmission current is not flowing, to thereby allow the reference current to flow from the constant current circuit to the current detection resistor, and generate a reference voltage, in which a threshold voltage corresponding to the reference current is added to a load current detection voltage corresponding to the load current; a capacitor which is connected to the current detection resistor via the first switch; a second switch which performs a switching operation in synchronization with the first switch to thereby sample-hold the reference voltage generated by the current detection resistor in the capacitor; and a
  • the constant current circuit supplies current, which generates a threshold voltage being 1 ⁇ 2 of the transmission current detection voltage corresponding to the transmission current, as the reference current.
  • a threshold voltage for detecting transmission current which is transmitted from a slave device and is received while being added on a load current is determined by means of a predetermined reference current flowed by a constant current source. Therefore the threshold value can be set to an arbitrary value. Moreover, since the current is supplied from a constant current source, the threshold voltage does not change due to temperature, and the transmission current can be reliably detected so that a high level of reliability can be ensured.
  • FIG. 1 is a block diagram showing a receiving device together with an analog type sensor and a relay device, in a monitoring system to which the present invention is applied.
  • FIG. 2 is a circuit diagram showing an embodiment of a transmission input circuit of the present invention.
  • FIG. 3 is a time chart showing comparator input voltage and sample-hold timing in the embodiment of FIG. 2 .
  • FIG. 4 is a time chart showing comparator input voltage and sample-hold timing in a case where load current is stable.
  • FIG. 5 is a time chart showing comparator input voltage and sample-hold timing in a case where load current varies.
  • FIG. 6 is a system block diagram showing a conventional monitoring system.
  • FIG. 7 is a block diagram showing, with an equivalent circuit, a relay device and an analog type sensor in the conventional monitoring system.
  • FIG. 8 is a circuit diagram showing a conventional transmission input circuit.
  • FIG. 9 is a time chart showing comparator input voltage and sample-hold timing in the conventional transmission input circuit shown in FIG. 8 .
  • FIG. 10 is a time chart showing comparator input voltage and sample-hold timing in the conventional transmission input circuit in a case where load current is stable.
  • FIG. 1 is a block diagram showing a configuration of a receiving device together with an analog type sensor and a relay device, in a monitoring system to which the present invention is applied.
  • an analog type sensor 14 and a relay device 16 serving as slave devices are severally connected to transmission lines 12 a and 12 b which are led out from a receiver device 10 serving as a master device, towards a monitoring area.
  • the analog type sensor 14 and the relay device 16 are provided with a transmission function which transmits and receives upstream signals and downstream signals to and from the receiver device 10 .
  • a unique address with a maximum of 127 addresses per transmission line, is preliminarily assigned to the analog type sensor 14 and to the relay device 16 .
  • the analog type sensor 14 detects a concentration of smoke (smoke concentration) occurring due to a fire hazard or a temperature (room temperature for example), and transmits the detected value to the receiving device 10 as analog data. Meanwhile, in the receiver device 10 , the presence or absence of a fire hazard occurrence is determined based on the received analog data of the smoke concentration or temperature, and a warning is issued if an occurrence of a fire hazard is determined.
  • the relay device 16 is provided so as to connect a plurality of ON/OFF type sensors 20 , which do not have a transmission function, to the transmission lines 12 a and 12 b .
  • the relay device 16 has a function to perform transmission to and from the receiver device 10 .
  • Each of the ON/OFF type sensors 20 is connected to sensor lines 18 a and 18 b led out from the relay device 16 .
  • the ON/OFF type sensor 20 when a fire hazard is detected, supplies an alarm current between the sensor lines 18 a and 18 b , and this alarm current is received by the relay device 16 , and fire hazard alarm data indicating a fire hazard occurrence is transmitted to the receiver device 10 .
  • the receiver device 10 sequentially specifies a slave device address at a constant polling cycle, and transmits a polling signal.
  • This polling signal is transmitted as a voltage pulse which varies the voltage between the transmission lines 12 a and 12 b between 18 volt and 30 volt for example.
  • upstream signals transmitted from the analog type sensor 14 and the relay device 16 to the receiver device 10 are transmitted in a current mode. That is to say, a signal current is supplied between the transmission lines 12 a and 12 b at the timing of bit 1 of the transmission data, and an upstream signal is transmitted to the receiver device 10 as a so-called current pulse sequence, and transmission current flows at this time.
  • the transmission lines 12 a and 12 b are also used as power supply lines for the analog type sensor 14 and the relay device 16 serving as slave devices. That is to say, in the transmission lines 12 a and 12 b , the supply voltage is varied in a range between 18 volt and 30 volt at the time of downstream signal transmission in the voltage mode, and at least voltage supply at 18 volt is performed. That is to say, power supply is continuously performed from the receiver device 10 serving as a master device, to the analog type sensor 14 and the relay device 16 serving as slave devices.
  • Electric power supplied through the transmission lines 12 a and 12 b is also supplied via the relay device 16 to the sensor lines 18 a and 18 b led out from the relay device 16 .
  • electric power is supplied to each of the ON/OFF type sensors 20 via the sensor lines 18 a and 18 b.
  • the receiver device 10 there are provided a CPU 22 and a transmission circuit section 24 corresponding to the CPU 22 . Moreover, the transmission lines 12 a and 12 b are led out from the transmission circuit section 24 .
  • the transmission output circuit 26 outputs a downstream signal to the transmission lines 12 a and 12 b in the voltage mode, based on a command instruction such as a polling instruction from the CPU 22 .
  • the transmission input circuit 28 When the transmission input circuit 28 receives an upstream signal transmitted in the current mode from the analog type sensor 14 or the relay device 16 serving as a slave device, that is, a transmission current, it outputs a transmission current detection signal indicating this reception to the CPU 22 , which makes the CPU 22 perform a fire hazard warning operation.
  • a display section 30 to correspond to the CPU 22 , there are provided a display section 30 , an operation section 32 , a memory section 34 , and an transferring section 36 , and various types of operations required for fire hazard monitoring including; warning output, warning display, operation, memorizing monitoring information, and information transfer signal output, can be performed.
  • a CPU 38 there are provided a sensor 38 , a sensor section 40 , and a transmission circuit section 42 .
  • the sensor section 40 detects a concentration of smoke (smoke concentration) occurring due to a fire hazard occurrence, or a temperature, and outputs it to the CPU 38 .
  • the transmission circuit section 42 receives a downstream signal of a polling command which specifies its own address from the receiver device 10 , and if the CPU 38 determines normality, an upstream signal indicating normality is transmitted to the receiver device 10 in the current mode.
  • the CPU 38 transmits a fire hazard alarm signal, which is a fire hazard interruption upstream signal, to the receiver device 10 so as to respond to the polling command which specified its own address.
  • the relay device 16 there are provided a CPU 44 , an alarm receiving section 46 , and a transmission circuit section 48 .
  • the sensor lines 18 a and 18 b are led out from the alarm receiving section 46 , and each ON/OFF type sensor 20 is connected as a load to these sensor lines 18 a and 18 b.
  • the ON/OFF type sensor 20 detects a fire hazard occurrence
  • an alarm current is supplied between the sensor lines 18 a and 18 b , and the alarm receiving section 46 receives this alarm current and output it to the CPU 44 . Consequently, by means of the transmission circuit 48 , the CPU 44 transmits a fire hazard interruption upstream signal to the receiver device 10 so as to respond to the polling command, which specified its own address.
  • the relay device 16 when a downstream signal of the polling command from the receiver device 10 specifying its own address is received, the relay device 16 also transmits an upstream signal indicating normality to the receiver device 10 in the current mode if there is no abnormality.
  • the receiver device 10 When normal monitoring is being performed, the receiver device 10 is transmitting a polling command for normal monitoring which sequentially specifies the address of the slave device.
  • the analog type sensor 14 and the relay device 16 perform a normal monitoring response when a polling command which matches their own set address is received. Accordingly, based on the presence or absence of a response to the polling command, the receiver device 10 can detect the presence or absence of failure in the analog type sensor 14 or the relay device 16 .
  • the analog type sensor 14 receives a batch AD conversion command which is repeatedly output at a cycle of polling command transmission of the receiver device 10 , to all of sensor addresses.
  • the analog type sensor 14 by means of a fire hazard detection mechanism (sensor section 40 ) provided therein, samples analog detection data such as smoke concentration and temperature, compares it with a pre-defined fire hazard level, and determines a fire hazard occurrence detection if it exceeds this fire hazard level.
  • the analogy type sensor 14 when a fire hazard occurrence is determined from the sampling result based on the batch AD conversion command, it transmits a fire hazard interruption signal to the receiver device 10 at the subsequent polling command transmission timing which specifies its own sensor address.
  • the fire hazard interruption signal there is used a signal which is not normally used such as one which sets all response bits to 1.
  • the relay device 16 also samples the state of reception performed by the alarm receiving section 46 based on the batch AD conversion command from the receiving device 10 . When the alarm reception is detected, the relay device 16 transmits a fire hazard interruption signal to the receiving device 10 at the subsequent timing where a polling command which specifies its own sensor address is transmitted.
  • the receiving device 10 When the receiving device 10 receives the fire hazard interruption signal from the analog type sensor 14 or the relay device 16 , it issues a group search command, and receives a fire hazard interruption response from the group including the analog type sensor 14 or the relay device 16 which has detected a fire hazard, to thereby determine the group. Subsequently, the receiving device 10 sequentially specifies the address of each of the analog type sensor 14 and the relay device 16 included in the determined group, performs polling with respect thereto, and receives a fire hazard response (analog data or fire hazard alarm data), to thereby recognizes the sensor address of the analog type sensor 14 or the relay device 16 which has detected the fire hazard, and perform a fire hazard warning operation.
  • a fire hazard response analog data or fire hazard alarm data
  • the analog type sensors 14 and the relay devices 16 of a maximum 127 units connected to the transmission lines 12 a and 12 b have a group address set to each 8 units thereof for example.
  • a fire hazard interruption response from the group which includes the analog type sensor 14 which has detected the fire hazard occurrence.
  • FIG. 2 is a circuit diagram showing a configuration of the transmission input circuit 28 according to one embodiment of the present invention.
  • the transmission input circuit 28 provided in the receiving device 10 is provided with; a current detection resistor R 1 , a comparator 48 , a capacitor C 1 , a first switch SW 1 , a second switch SW 2 , a constant current circuit 50 , and a pull-up resistor R 2 .
  • a load current Iz flows to the negative side transmission line 12 b where the relay device 16 shown in FIG. 1 serves as a constant load for example. Furthermore, as a response to the polling performed by the analog type sensor 14 or the relay device 16 shown in FIG. 1 , a transmission current Ia flows to the transmission line 12 b at constant intervals.
  • the current detection resistor R 1 is connected to the negative input terminal of the comparator 48 .
  • To the positive input terminal of the comparator 48 there is connected the capacitor C 1 .
  • the capacitor C 1 is connected via the first switch SW 1 , to an input line of the negative input terminal of the comparator 48 , to which the current detection resistor R 1 is connected.
  • To the input line for the negative input terminal and the positive input terminal of the comparator 48 there is connected via the second switch SW 2 , the constant current circuit 50 on the power supply line of the power supply voltage Vc.
  • the first switch SW 1 and the second switch SW 2 are turned ON and OFF at an empty timing of transmission current from the slave device, under control performed by the CPU 22 .
  • the load current Iz serving as a base current due to the load of the relay device 16 shown in FIG. 1 flows. Therefore a load current detection voltage Vz corresponding to the load current Iz is produced in the current detection resistor R 1 .
  • the first switch SW 1 and the second switch SW 2 are turned ON during a period of time between time t 1 and time t 2 at the empty timing where there is no transmission current from the slave device.
  • time t 1 which is a sample-hold timing
  • the line current is only the load current Iz due to the load of the relay device 16 or the like shown in FIG. 1 . Therefore only the load current detection voltage Vz corresponding to the load current Iz is produced in the current detection resistor R 1 .
  • the reference voltage Vr to be sample-held in the capacitor C 1 of the comparator 48 is arbitrarily adjusted, and the constant current Ie is adjusted so that preferably as shown in FIG. 3 (A), a threshold voltage Ve which is half of the transmission current detection voltage Va can be obtained.
  • FIG. 4 (A) and (B) of FIG. 4 are time charts showing the input voltage to the comparator 48 and the sample-holding timing in a case where the load current Iz is stable.
  • FIG. 4 (A) shows the line current detection voltage to be input to the comparator 48 .
  • the load current detection voltage Vz is constant, and the transmission current detection voltage Va is added in a state of being added thereto.
  • the reference voltage Vr ⁇ (Vz+Ve) is set so that the threshold voltage Ve becomes half of the change in the transmission current detection voltage Va.
  • FIG. 5 are time charts showing the input voltage to the comparator 48 and the sample-holding timing in a case where the load current Iz varies.
  • the comparator input voltage shown with FIG. 5 (A) indicates that the load current Iz due to the relay device 16 shown in FIG. 1 changes over time, and as a result, the load current detection voltage Vz varies. In a state of being added to the load current detection voltage Vz which changes in this fashion, there is produced the transmission current detection voltage Va based on the transmission current Ia supplied from the slave device at constant intervals.
  • the reference voltage Vr is set to a value in which a threshold voltage Ve corresponding to the constant current Ie supplied by the constant current circuit 50 is added to the load current detection voltage at the time of the sample-holding. Consequently the threshold voltage Ve is always constant although the reference voltage Vr changes so as to follow the changes in the load current detection voltage Vz. Therefore it is possible to maintain the reference voltage Vr at an optimum level which is half of the transmission current detection voltage Va produced in a state of being added to the load current detection voltage Vz. Hence it is possible to reliably detect transmission current even when the load current Iz changes.
  • the case of connecting the relay device 16 as a constant load for the transmission lines 12 a and 12 b is taken as an example.
  • the case of connecting a gas leakage alarm or a theft alarm via a relay device 16 is similar to this case.
  • the present invention includes appropriate modified examples which do not impair the object and advantage thereof. Further, it is not limited by just the numerical values illustrated in the above embodiment.
  • a threshold voltage for detecting transmission current which is transmitted from a slave device and is received while being added to a load current, is determined with a predetermined reference current flowed by a constant current source. Therefore the threshold value can be set to an arbitrary value. Moreover, since it is supplied from a constant current source, the threshold voltage does not change due to temperature, transmission current can be reliably detected, and a high level of reliability can be ensured.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Security & Cryptography (AREA)
  • Fire Alarms (AREA)
  • Alarm Systems (AREA)
  • Arrangements For Transmission Of Measured Signals (AREA)
US13/121,866 2008-10-02 2009-10-02 Transmission input circuit Active 2029-10-31 US8362808B2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP2008-257172 2008-10-02
JP2008257172 2008-10-02
JP2008257172 2008-10-02
PCT/JP2009/005116 WO2010038480A1 (ja) 2008-10-02 2009-10-02 伝送入力回路

Publications (2)

Publication Number Publication Date
US20110187415A1 US20110187415A1 (en) 2011-08-04
US8362808B2 true US8362808B2 (en) 2013-01-29

Family

ID=42073258

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/121,866 Active 2029-10-31 US8362808B2 (en) 2008-10-02 2009-10-02 Transmission input circuit

Country Status (6)

Country Link
US (1) US8362808B2 (ja)
EP (1) EP2352134B1 (ja)
JP (1) JP5275360B2 (ja)
CN (1) CN102105917B (ja)
AU (1) AU2009298996B2 (ja)
WO (1) WO2010038480A1 (ja)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5939826B2 (ja) * 2012-02-14 2016-06-22 能美防災株式会社 火災報知設備
CN102981991A (zh) * 2012-11-13 2013-03-20 四川和芯微电子股份有限公司 串行数据传输系统及方法
JP5962593B2 (ja) * 2013-06-07 2016-08-03 株式会社デンソー 電流検出装置
US9225249B2 (en) * 2014-01-28 2015-12-29 Honeywell International Inc. Power management alarm devices
JP6464519B2 (ja) * 2014-04-18 2019-02-06 パナソニックＩｐマネジメント株式会社 自動火災報知システムの子機、およびそれを用いた自動火災報知システム
CN104375547B (zh) * 2014-09-05 2016-01-06 四川和芯微电子股份有限公司 检测终端负载的系统
JP6566353B2 (ja) * 2015-08-07 2019-08-28 パナソニックＩｐマネジメント株式会社 自動火災報知システムの子機、自動火災報知システム、および自動火災報知システムの親機
CA3079768C (en) * 2017-12-01 2024-03-19 Tendyron Corporation Data transmitting circuit and apparatus, and data receiving circuit and apparatus

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62276694A (ja) 1987-05-18 1987-12-01 ホーチキ株式会社 火災警報装置
US5266884A (en) * 1992-05-04 1993-11-30 Cherry Semiconductor Corporation Threshold controlled circuit with ensured hysteresis precedence
US5274273A (en) * 1992-01-31 1993-12-28 Sperry Marine Inc. Method and apparatus for establishing a threshold with the use of a delay line
JPH06301876A (ja) 1993-04-13 1994-10-28 Hochiki Corp 防災監視装置
JPH0991576A (ja) 1995-09-26 1997-04-04 Matsushita Electric Works Ltd 火災受信機による感知器回線断線検出システム
US6215334B1 (en) * 1997-10-24 2001-04-10 General Electronics Applications, Inc. Analog signal processing circuit with noise immunity and reduced delay
JP2004102888A (ja) 2002-09-12 2004-04-02 Hochiki Corp 防災受信機
US20050162207A1 (en) * 2004-01-27 2005-07-28 Denso Corporation Hysteresis comparator circuit
US7102396B2 (en) * 2003-09-16 2006-09-05 Sony Corporation Hysteresis detecting method, hysteresis detecting circuit and mobile device

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2735174B2 (ja) * 1985-10-16 1998-04-02 株式会社日立製作所 ２線式通信方法
SE457176B (sv) * 1986-04-07 1988-12-05 Electrolux Ab Lokalt system foer oevervakning och styrning av i ett hem foerekommande apparater, larmanordningar o d
JPH0633723Y2 (ja) * 1987-09-03 1994-08-31 山武ハネウエル株式会社 通信装置
JP3116250B2 (ja) * 1992-04-09 2000-12-11 能美防災株式会社 火災報知設備
US6125334A (en) * 1997-05-02 2000-09-26 Texas Instruments Incorporated Module-configurable full-chip power profiler

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62276694A (ja) 1987-05-18 1987-12-01 ホーチキ株式会社 火災警報装置
US5274273A (en) * 1992-01-31 1993-12-28 Sperry Marine Inc. Method and apparatus for establishing a threshold with the use of a delay line
US5266884A (en) * 1992-05-04 1993-11-30 Cherry Semiconductor Corporation Threshold controlled circuit with ensured hysteresis precedence
JPH06301876A (ja) 1993-04-13 1994-10-28 Hochiki Corp 防災監視装置
JPH0991576A (ja) 1995-09-26 1997-04-04 Matsushita Electric Works Ltd 火災受信機による感知器回線断線検出システム
US6215334B1 (en) * 1997-10-24 2001-04-10 General Electronics Applications, Inc. Analog signal processing circuit with noise immunity and reduced delay
JP2004102888A (ja) 2002-09-12 2004-04-02 Hochiki Corp 防災受信機
US7102396B2 (en) * 2003-09-16 2006-09-05 Sony Corporation Hysteresis detecting method, hysteresis detecting circuit and mobile device
US20050162207A1 (en) * 2004-01-27 2005-07-28 Denso Corporation Hysteresis comparator circuit

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
International Search Report issued on PCT application No. PCT/JP2009/005116, mailed on Jan. 12, 2010.

Also Published As

Publication number Publication date
EP2352134A1 (en) 2011-08-03
JP5275360B2 (ja) 2013-08-28
JPWO2010038480A1 (ja) 2012-03-01
CN102105917A (zh) 2011-06-22
CN102105917B (zh) 2013-01-16
US20110187415A1 (en) 2011-08-04
EP2352134B1 (en) 2018-09-05
EP2352134A4 (en) 2018-01-17
AU2009298996B2 (en) 2014-11-20
AU2009298996A1 (en) 2010-04-08
WO2010038480A1 (ja) 2010-04-08

Similar Documents

Publication Publication Date Title
US8362808B2 (en) Transmission input circuit
AU2014212834B2 (en) Programmable interface circuit for coupling field devices to process controllers
US8294474B2 (en) Device for sensing a fault current in a field bus system
US8373445B2 (en) Transmission input circuit
US10937299B2 (en) Current diagnostics for field devices
US20060100759A1 (en) Control unit for controlling and/or regulating at least one vehicle function
US10718642B2 (en) Method for checking the operability of measuring transducers
US10581622B2 (en) Communication device and communication system
CN107024237B (zh) 具有至少两个外围单元和一个传感器的装置
CN212133911U (zh) 一种菊花链二线制温度测量系统
JP2018185612A (ja) 通信回路、通信システム及び通信回路の自己診断方法
US11391772B2 (en) Signal transmission system
JP5231152B2 (ja) 伝送入力回路とその制御回路を備えた親機
JP4740547B2 (ja) 火災報知システム
US20230245508A1 (en) Sensing Assembly Having a Multiplexer
JP5240841B2 (ja) 伝送入力回路とその制御回路を備えた親機
CN220064803U (zh) 一种数据传输系统及终端设备
CN112055817B (zh) 具有电路中断识别的冗余的电流测量装置
CN113196347B (zh) 火灾报警设备和升压器
JP3785534B2 (ja) 火災受信中継器および火災受信機
JP4440955B2 (ja) 接点出力装置
JP2007336332A (ja) 伝送器
JPH02284540A (ja) 遠方監視制御方式
KR980006719U (ko) 화재감지회로

Legal Events

Date Code Title Description
AS Assignment

Owner name: HOCHIKI CORPORATION, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:KURIMOTO, MITSUHIRO;REEL/FRAME:026128/0178

Effective date: 20110322

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STCF Information on status: patent grant

Free format text: PATENTED CASE

FPAY Fee payment

Year of fee payment: 4

MAFP Maintenance fee payment

Free format text: PAYMENT OF MAINTENANCE FEE, 8TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1552); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

Year of fee payment: 8